'Twilight' Hunk Kellan Lutz Shy About Posing in Nothing But His Calvins

Kellan Lutz may have abs to rival his ripped co-star Taylor Lautner, but the Twilight actor was nervous about stripping off to his skivvies in the steamy new Calvin Klein underwear ads.

“I’ve never had to do anything like that, so in the beginning, I was just, like, ‘So, is the temperature going to be hot? Do I need, you know, fluffers maybe?'” Kellan said, describing his worries ahead of the shoot.